Beryl Mountain, Sullivan County, New Hampshire (open access)

Beryl Mountain, Sullivan County, New Hampshire

Report issued by the Bureau of Mines over exploration of mineral deposits on Beryl Mountain. As stated in the introduction, "testing by surface cuts, trenching, and tunneling was conducted by the Bureau of Mines from August to December 1943" (p. 1). This report includes maps.
Date: March 1948
Creator: Levin, S. B.
System: The UNT Digital Library
United States Earthquakes 1940 (open access)

United States Earthquakes 1940

Report discussing earthquake activity in the United States during 1940. The report is broken down by regions and has sections for specific earthquakes.
Date: 1940
Creator: unknown
System: The UNT Digital Library
Mica-Bearing Pegmatites of New Hampshire: a Preliminary Report (open access)

Mica-Bearing Pegmatites of New Hampshire: a Preliminary Report

From abstract: Mica has been mined in New Hampshire since 1803. Production from 1908 through 1939 has aggregated 13,326,990 pounds of sheet and punch mica, an annual average of 416,470 pounds. Since 1931 production has been below this average, because of economic conditions rather than depletions. The mica-bearing pegmatites of the Grafton and Keene districts occur mostly in sillimanite-mica schist adjacent to large areas of biotite gneiss. The pegmatite bodies range from a fraction of an inch to more than 200 feet in thickness; most of them are crosscutting, and about 75 percent strike northeast. Mica occurs sporadically in most of them but where present in commercial quantities it is localized in one or more of the following zones: (1) In quartz-plagioclase-muscovite zones 2 to 10 feet from the walls of large pegmatite bodies, (2) in or near quartz masses that occur mostly near the centers of the bodies, (3) in thin dikes 5 to 15 feet thick or in similar offshoots from larger bodies, (4) within large pegmatite bodies, in more or less tabular streaks or zones composed principally of plagioclase, quartz, and muscovite.
Date: 1942
Creator: Olson, J. C.
System: The UNT Digital Library